TITLE:
The Controlling of Deformation Basing on Strain Partitioning Model: Case Study to Gafsa Basin (Southern Tunisian Atlas)
AUTHORS:
Soulef Amamria, Mohamed Sadok Bensalem, Mohamed Ghanmi, Fouad Zargouni
KEYWORDS:
Strain Partitioning, Gafsa Chains, Triassic Decollement Level, Thin and Tick Skinned
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.3 No.1,
March
25,
2015
ABSTRACT: One of the
principal parameters to study the tectonics deformation is the relation between
the shortening axis and the direction of preexistent principal fault. It is important
to verify this parameter in the belts structures. The aim of this contribution is
to check this notion in the Atlassic structures, especially in the southern
limit of Tunisian Atlas: Gafsa fault. The strain partitioning model proposed in
the interpretation of geodynamics of Gafsa chains suggests the coexistence of thrusting
and strike-slip faults during the same tectonics phase. The application of this
model requires a particular geometry between the shortening axis and the
direction of fault, and indeed the obliquity of preexistent faults by the
reported shortening axis interprets us a transpressive context. The slickenside
examination shows the coexistence of thrusting and strike-slip faults. The application
of model of strain partitioning requires a decollement level which is confirmed
in the Gafsa basin by the upper level of Triassic series. These parameters
confirm a particular relation thin and thick-skinned and the maximum of deformation
is cover, although the basement structures permeate simple passive transport of
the deformation along the Triassic decollement level. These problems confirm
the assumption of the evolution of the shortening axis during geological events
and especially the rotation of Africa and Eurasia.